Question

我正在尝试在Java应用程序中建立与firebase的基本连接，并且使用提供的基本代码我根本无法获得任何响应。

以下是我正在使用的代码：

package fix;

import com.firebase.client.*;

public class Main {

  public static void main(String args[]) throws Exception {

    String url = "https://----.firebaseIO.com/";
    Firebase dataRef = new Firebase(url);

    dataRef.addListenerForSingleValueEvent(new ValueEventListener() {
         @Override
         public void onDataChange(DataSnapshot snapshot) {
             System.out.println("data");
         }

         @Override
         public void onCancelled() {
             System.err.println("Listener was cancelled");
         }
    });

    System.out.println("hi");
  }
}

图书馆似乎装得很好。有什么建议吗？

更新

[java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Raising events for /.info/authenticated
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Doing onDiff with changes: []
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/authenticated
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/authenticated
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queryMap complete:null
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/authenticated
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queryMap complete:null
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Raising events for /.info/connected
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Doing onDiff with changes: []
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/connected
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/connected
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queryMap complete:null
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queries complete for /.info/connected
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Marking queryMap complete:null
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] ViewManager: Adding Value Event Listener callback for path: /
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] PersistentConnection: pc_0 - Listening on / for [{}]
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] PersistentConnection: pc_0 - Adding listen params: [{}]
 [java] Fri Sep 06 09:54:43 PDT 2013 [DEBUG] EventRaiser: Raising 0 event(s)
 [java] wait
 [java] wait
 [java] wait
 [java] wait

Answer 1

我认为问题在于，与持续运行等待事件和回调触发的Node.js不同，Java在到达main方法结束时退出。你想要让主线程退出。这样的事情应该使主线程不会终止。

while(true) {
     Thread.Sleep(10000); //Sleep 10 seconds
}

Answer 2

Firebase工程师在这里，您可以启用日志记录并发布输出吗？您可以通过执行以下操作启用日志记录：

Firebase.getDefaultConfig().setLogLevel(Logger.Level.DEBUG);

另外，您可以为

添加观察者吗？

dataRef.child(".info/connected");

并记录您从中获得的事件？这将告诉您何时连接或与Firebase断开连接。

编辑：这是通过电子邮件解决的。这是客户端库中的一个错误，现在已经解决了。您可以从网站下载最新版本：https://www.firebase.com/docs/downloads.html

基本Firebase Java连接

2 个答案: